28 EXPLANATION OF THE PLATES. 
6. From the original figure in Brit. Pal. Foss., pl. i. B, fig. 24, showing the 
“‘ calice” or cup with the ‘‘ septa,” uniting towards the centre. 
The corals referred to Petraia and Turbinolopsis, usually in the state of 
casts, appear many of them to belong to Cyathophyllum, Brit. Foss. Co- 
_ rals (Paleontographical Society), p. 286. 
Carapoc or Bara Rocxs.—Coniston, Westmoreland; Ayrshire ; Lanca- 
shire; North Wales. Catal. Brit. Foss., p. 62. In the Appendix to Si- 
luria, third edition, it is inserted as ranging into the Llandovery Rocks. 
ANNELIDA. 
Fic. 3.—a, 6. Tenracurires AneGuicus, Salter. 
T. annulatus and scalaris, Silurian System, pl. xix., figs. 15,16. 7. Anglicus, 
Siluria, third edition, p. 74; Foss. 12, fig. 4. 
a. Original. A piece of fine laminated sandstone, full of these small but very 
characteristic fossils, in Museum Geol. Surv. of Ireland. Caradoc Sand- 
stone, Cheney Longville, Shropshire. 
b. Original. Portion of one of these fossils, enlarged ; the upper part being an 
impression, showing a regular series of rings or annular ridges, from which 
the cast which fills up the lower part has fallen out. 
Carapoc or Bata To LuAnpovery Rocxs.—Appendix to Siluria, third 
edition, p. 537. Localities: Shropshire; North and South Wales; Tort- 
worth ; Coniston ; Malverns (Cat. of Brit. Foss., 2nd edition, p. 94). Cara- 
doc ; several localities in Caernarvonshire, Merionethshire, Montgomery- 
shire, and Denbighshire. Mem. Geol. Surv., vol. iii., p. 261. Bala beds, 
Slieveroe, Co. Wicklow, W. H. B. 
This well-marked little fossil is very abundant, and eminently charac- 
teristic of strata of Caradoc or Bala age. 
ECHINODERMATA.—CYSTIDE 2. 
Fic. 4.—a, 6, c. SpHaRonITES Lircut, Forbes, sp. 
ee i Intchi, Forbes, Mem. Geol. Surv., vol. ii., part ii., p. 514, pl. 
xxl., figs. 2 a-g. 
a. From the Bical figure in the volume above cited, pl. xxi., fig. 2b, which 
is repeated in vol. ii1., pl. xx., fig.3. Part of the test or shell of this globular 
cystidean having been removed, shows it to be composed of large hexago- 
nal plates; at the summit are two projections for the oral and anal ori- 
fices ; traces of the ovarian aperture may be seen at the upper part of the 
body, near the mouth. 
b, c. Original. Enlarged views of the external markings, from the natural 
impression of one of these bodies, labelled Caryocystites Litchi in the mu- 
seum, Geological Survey of Ireland; fig. 4 b, showing the twin pores de- 
seribed by Professor’ Forbes, vol. i1., part ii., p. 514, is taken from the 
natural impression, and corresponds with 2 e and f of the original figures 
illustrating Professor Forbes’ Memoir. 4 ce. Enlarged markings from the 
surface of the cast, which came out of the impression, showing pairs of 
pores, enclosed, by small irregular hexagonal spaces, corresponding with 
figure 2 d of pl. xxi., in the vol. before cited. 
Carapoc or Bara.—Bala, Merionethshire, North Wales; Sholes Hook, 
Pembrokeshire, South Wales. 
